Broadband antireflection coatings can be made from multi-layer stacks or by microstructuring the surface. One approach for microstructuring is to prepare random rough surfaces by sputtering or evaporation technology. A second is the production of periodic holographic double gratings, so-called `moth eyes' with spatial periods of less than 1 micrometers . The effect of these two possibilities on the solar absorptance is demonstrated by the example of cermet solar absorber coatings.